// 设置常见的屏幕尺寸，修改里面的html文字大小
html {
    font-size: 50px;
} 
//划分 15等分;
$no: 15;
//320
@media screen and (min-width: 320px){
    html {
        font-size: 320px / $no;
    }
}
//360px
@media screen and (min-width: 360px){
    html {
        font-size: 360px / $no;
    }
}
//375px
@media screen and (min-width: 375px){
    html {
        font-size: 375px / $no;
    }
}
//384px
@media screen and (min-width: 384px){
    html {
        font-size: 384px / $no;
    }
}
//400px
@media screen and (min-width: 400px){
    html {
        font-size: 400px / $no;
    }
}
//414px
@media screen and (min-width: 414px){
    html {
        font-size: 414px / $no;
    }
}
//424px
@media screen and (min-width: 424px){
    html {
        font-size: 424px / $no;
    }
}
//480px
@media screen and (min-width: 480px){
    html {
        font-size: 320px / $no;
    }
}
//540px
@media screen and (min-width: 540px){
    html {
        font-size: 540px / $no;
    }
}
//720px
@media screen and (min-width: 720px){
    html {
        font-size: 720px / $no;
    }
}
//750px
@media screen and (min-width: 750px){
    html {
        font-size: 750px / $no;
    }
}